Controlling Algae in your Aquarium

1. Not all algae is bad. A certain amount is to be expected. Algae needs water, light and food live. The following guidelines will help to keep algae under control :

1. Avoid direct sunlight on your aquarium.
2. Don't leave the lights on your aquarium on more than 8 hours. Six to eight hours of light is recommended.
3. Keep nitrates, phosphates and silicates at a low level. If you have a persistent problem - use reverse osmosis (RO) or deionised (DI) water, or specific adsorption resins (e.g. PhosGuard). However, note that although high levels of such nutrients may encourage algae, it is not generally possible to completely eliminate algae by attempting to reduce them, as algae can survive at levels below those which can be measured by a hobbyist test kit.
4. Consider adding algae eating fish, such as

•  the Bushy Nose Pleco http://www.aquariumfish.net/catalog_pages/scavengers/plecostomus.htm#top2

•  Siamese Algae Eater http://www.thetropicaltank.co.uk/Fishindx/sae.htm

•  Chinese Algae Eater http://members.tripod.com/~Boeing_Dude/cae.html

Types of Algae http://www.aquaticscape.com/articles/algae.htm#types

Blue-green, slime or smear algae http://www.aquaticscape.com/articles/algae.htm#bluegreen

Grows rapidly in blue-green, slimy sheets. Spreads rapidly over almost everything and usually indicates poor water quality. However, blue-green algae can fix nitrogen and may be seen in aquariums with extremely low nitrates. Sometimes seen in small quantities between the substrate and aquarium sides. Will smother and kill plants. This is actually cyanobacteria. It can be physically removed, but this is not a viable long term solution as the aquarium conditions are still favorable for it and it will return quickly. Treatment with 200 mg of erythromycin phosphate per 10 gallons of water will usually eliminate blue-green algae but some experts feel it may also have adverse effects on the biological filter bed. If erythromycin is used for treatment, ammonia and nitrite levels should be carefully monitored.

Brown algae http://www.aquaticscape.com/articles/algae.htm#brown

Forms in soft brown clumpy patches. In the freshwater aquarium, these are usually diatoms. Usually indicates a lack of light or an excess of silicates. Increased light levels will usually make it disappear. Easily removed by wiping the glass or siphon vacuuming the affected area.

Green water http://www.aquaticscape.com/articles/algae.htm#greenwater

Green unicellular algae will sometimes reproduce so rapidly that the water will turn green. This is commonly called an "algae bloom" and is usually caused by too much light like direct sunlight. An algae bloom can be removed by filtering with micron cartridges or diatom filters. UV sterilizers can prevent the bloom in the first place. Green water is very useful in the raising of daphnia and brine shrimp. Film algae Grows on the aquarium glass and forms a thin haze. Easily removed by wiping the glass. Considered normal with the higher light levels needed for good plant growth.

Spot algae http://www.aquaticscape.com/articles/algae.htm#Spot

Grows in thin, hard, circular, bright green spots, usually on the aquarium glass but also on plants under high light conditions. Considered normal for planted tanks. Must be mechanically removed. On acrylic aquariums, use a cloth pad or a gentle scouring pad like a cosmetic "Buff-Puff" and a lot of elbow grease. On glass tanks, scraping with a razor blade is most effective.

Fuzz algae http://www.aquaticscape.com/articles/algae.htm#fuzz

Grows mostly on plant leaves as separate, short (2-3mm) strands. Considered normal. It might be a less "virulent" form of "beard" algae. Easily controlled with algae eaters such as black mollies, Otocinclus, Peckoltia and siamese algae eaters.

Hair algae http://www.aquaticscape.com/articles/algae.htm#hair

Grows in bright green clumps in the gravel, around the base of plants like Echinodorus and around mechanical objects. It has a coarser texture than "beard algae". Beard algae will ripple in the water current, hair algae tends to form matted clumps. Individual strands can get to 5 cm or more. This is easy to remove mechanically by twirling a toothbrush in it. Can be troublesome if left unchecked. This is a popular food supplement for fish among European aquarists.

Thread algae http://www.aquaticscape.com/articles/algae.htm#thread

Grows in long, thin strands up to 30 cm or more. Tends toward a dull green color (hard to tell because it is so thin). Usually indicates an excess of iron (> 0.15 ppm). Easily removed with a toothbrush like hair algae.

Staghorn algae http://www.aquaticscape.com/articles/algae.htm#staghorn

Looks like individual strands of hair algae but tends to grow in single branching strands like a deer antler and is grey-green. Seems to grow mostly on tank equipment near the surface. Difficult to remove mechanically. Soak affected equipment in a 25% solution of household bleach and water to remove it.

Brush algae http://www.aquaticscape.com/articles/algae.htm#brush

This grows in feathery black tufts 2-3 mm long and tends to collect on slower growing leaves like Anubias, some Echinodorus and other wide leaf plants. Also tends to collect on mechanical equipment. This is actually a red alga in the genus Audouinella (other names: Acrochaetium, Rhodochorton, Chantransia). It cannot easily be removed mechanically. Remove and discard the affected leaves. Equipment can be soaked in a 25% bleach solution, then scrubbed to remove the dead algae. Siamese Algae Eaters (Crossocheilus siamensis) are known to eat this algae and can keep it in check. A more drastic measure is treatment with copper.

A really good article on this algae by Neil Frank
can be found at http://www.thekrib.com/Plants/Algae/red-algae.html